1. Technical Field
The present invention relates to a liquid container that is detachably mounted to a container mounting portion of a liquid consuming apparatus and supplies a liquid stored in a liquid containing portion to the liquid consuming apparatus.
2. Related Art
As a liquid container for containing a liquid used for a liquid consuming apparatus, for example, an ink cartridge used for an ink jet printer has been known. In the ink cartridge for the ink jet printer, an ink containing chamber having ink to be supplied to a printing head (a liquid containing portion) is provided in a container body, and the ink cartridge is detachably mounted to a cartridge mounting portion (a container mounting portion) provided at a predetermined position when it is used. The ink contained in the ink containing chamber is supplied to a printing head that is driven according to printing data transmitted from a host computer, and is then discharged at target positions onto a printing medium, such as a sheet, from nozzles provided in the printing head.
In general, the ink jet printer includes a carriage that has a printing head for discharging ink droplets and reciprocates in a direction orthogonal to the direction in which a printing medium is transported. In addition, ink can be supplied from the ink cartridge to the printing head by the following methods. First, an ink cartridge is detachably mounted to a cartridge mounting portion provided in the carriage, and ink is supplied to the printing head from the ink cartridge that is reciprocated together with the printing head (a so-called on-carriage type). Second, an ink cartridge is detachably mounted to a cartridge mounting portion that is separately provided from a carriage of the ink jet printer, and ink is supplied from the ink cartridge to the printing head through an ink passage formed of, for example, a flexible tube (a so-called off-carriage type).
Various types of ink cartridges including an ink cartridge disclosed in Patent Document 1 have been proposed as the ink cartridge mounted to an off-carriage type of ink jet printer.
An ink cartridge 201 shown in FIGS. 15 and 16 is disclosed in Patent Document 1. In the ink cartridge 201, an ink pack 209 whose volume can be reduced by pressure caused by pressurized air, which is supplied from a pressure chamber 207 of a container body 205, is accommodated in the container body 205 that is mounted to a cartridge mounting portion 203 of the ink jet printer, and the ink pack 209 contains ink used for the ink jet printer.
As shown in FIG. 16, one surface of the container body 205 (a leading end surface of the container body in a direction in which the container body is mounted) is provided with two positioning engaging portions (positioning means) 213 into which two positioning members 211 provided on the cartridge mounting portion 203 are fitted, thereby positioning the container body 205; an ink delivery port (a liquid delivery portion) 217 that connects an ink supply passage (a liquid supply portion) 215 of the cartridge mounting portion 203 to the ink pack 209; and a pressurized air inlet 221 that connects a pressurized air supply passage 219 of the cartridge mounting portion 203 to a pressure chamber 207. In the ink cartridge 201, the ink delivery port 217 is provided substantially at the center of one surface of the container body 205.
As shown in FIG. 17, in the ink pack 209, the ink delivery port 217 for delivering the ink contained in the ink pack 209 to the outside is provided in a flexible pouch 216. For example, the flexible pouch 216 is formed by overlapping two laminated films and bonding the edges of the laminated films by fusing.
Patent Document 1: JP-A-2002-19135
However, in recent years, with an increase in the size of a liquid container, errors in the formation or assembly of the container body 205 have increased, and the tolerance between the positioning engaging portion 213 and the ink delivery port 217 has increased.
When the ink cartridge 201 is mounted to the cartridge mounting portion 203, the positional accuracy between the ink supply passage 215 and the ink delivery port 217 is lowered. As a result, the ink supply passage 215 is not smoothly connected to the ink delivery port 217, and the mountability of the ink cartridge is likely to be lowered.
In addition, in recent years, the number of liquid containers mounted to the ink jet printer has increased in order to improve a printing quality. Therefore, it is assumed that the liquid container is vertically arranged in order to accommodate the liquid container at a high density.
In the structure in which the ink cartridge 201 is vertically arranged, when the amount of ink filled into the ink pack 209 increases due to an increase in the size of the liquid container, the internal pressure of the ink pack increases even when no pressure is applied. As a result, the leakage of ink from the ink delivery port 217 is likely to increase.